The present invention relates to a rectifier arrangement, and, more particularly, to a rectifier arrangement for a three-phase generator for a motor vehicle.
Rectifier arrangements for three-phase generators are known. If the three-phase generators are used, for example, to supply the electrical system in motor vehicles, the three-phase alternating current generated in the three-phase generators must be rectified because of the battery charging required in the motor vehicle. For this purpose, semiconductor power diodes are provided which are interconnected in a three-phase bridge connection. In this case, each half wave of each phase is assigned one diode, with the result that for full-wave rectification the three-phase bridge connection is formed from a total of six power diodes (see DE 40 18 710 A1, corresponding to U.S. Pat. No. 5,296,770). In this case, three positive diodes are connected for the positive side and three negative diodes for the negative side. It is known for the power diodes to be constructed as press-fit diodes, power diodes of like polarity respectively being pressed into one heat sink. The heat sinks are in this case sandwiched together, having an interposed insulating part which receives the electrical connections between the power diodes and the three-phase winding. A press-fit base of the press-fit diodes simultaneously undertakes in this case permanent thermal and electrical connection of the power diodes to the heat sink. However, it is possible to produce such a three-phase bridge connection comprising press-fit diodes only with a very high outlay. Furthermore, it is necessary there to have crimp connections welded or soldered to the terminals, in order to absorb thermal and mechanical stresses at the soldering or welding points.